1. Field of the Invention
The invention relates to a method for producing a same pattern and an installation for printing, coating and pressing two different base materials with the same pattern, which is covered with a synthetic resin and subsequently pressed therewith.
2. Discussion of Background Information
Base materials, in particular woodbased-material boards, provided with a pattern, are generally used as surface elements for cladding floors, walls and ceilings. In particular, when woodbased-material boards are used as floor-covering elements, wood grain, tile patterns, parquet imitations and fantasy patterns are used as patterns.
In particular, when the desired patterns are a single-piece production, the purchaser or customer would like to inspect the desired motif on a sample or sample workpiece before the entire batch is completed. Conventionally, a so-called proof paper is used for this purpose, i.e., the desired pattern is printed on a paper with the aid of an inkjet printer. This proof paper is then assessed for suitability and, if the outcome is positive, a further data set is produced with which, for instance, a print roller is produced which is used for the actual printing process of the pattern when printing the woodbased-material board.
However, with this approach the problem is encountered that the proof paper and the end product, the printed woodbased-material board, can ultimately produce a non-identical appearance of the pattern due to the different materials, paper or a woodbased-material board. The reason for this discrepancy is that, on the one hand, a different ink is used for printing the proof paper and, on the other hand, the application method in the form of printed dots (pixels) differs from the application of a printing ink onto a woodbased-material board generally carried out with the aid of an anilox roller.
Conventionally, a motif provided by a purchaser is converted into a data set which already contains a certain number of control parameters to control an inkjet printer. An inkjet printer is now operated with the aid of the data set to print the motif onto a decorative paper. A decorative paper obtained in this manner is submitted to the purchaser and, if it is approved, the existing data set is used to design a further data set that is used to engrave a print roller to be used for printing. An engraving of this type is preferably made with the aid of a laser.
The second data set is therefore already different with which the motif is now printed onto a woodbased-material board using correct printing ink, and this board is compared to the proof paper. If the comparison proves to be negative, and the two prints are not consistent, the data set is used to start another printing, which may also require one or more baby rollers to be split off. If a satisfactory printing on a woodbased-material board is now finally achieved, the woodbased-material board, e.g., to produce a flooring panel, is provided with an abrasion-resistant layer and pressed in a so-called short-cycle press.
The changes that are inevitably produced during pressing and the preceding coating necessitate another comparison of the proof paper with the end result regarding the optical appearance of the motif printed on the board. If unacceptable deviations are found, another attempt must be made to match the proof paper and the end result by changing the conditions prevailing during the coating and/or pressing process. A method of this type may be very time-consuming as well as ultimately cost-intensive.
It is known from EP 1 145 863 B1 to produce a sample print on an inkjet printer. The base material should resemble the gravure paper used for the serial print in terms of brilliance or degree of brightness and gloss. To this end, regular gravure paper is provided with an ink-receiving layer that is as transparent as possible.
It is known from the publication “Farbmanagement und Rastererhalt in einem Proof” in Druckspiegel (dated January 2003, pages 20 through 22) to control an inkjet printer with the same data set with which a printing plate is written. A test system of this type is known, e.g., in the “Digitaler Kontraktproof von Rasterdaten” data sheet.
The advantages and disadvantages of the raster proof, which depend on the print products and the customer requirements, are discussed in the journal www.value-magazine.de “Gerasteter Digitalproof,” April 2006.